Vertical Alignment of Panoramas with PTGui
Posted: Wed Apr 22, 2009 2:37 pmSome of the 360cities photographers have sometimes some problems with the correct vertical alignment of the panorama: To make this task clear and easy I would like to explain the process with a sample panorama and the corresponding screen shots. Reason for not perfect vertical alignment is a not vertically aligned tripod/monopod. But don't worry about it, you can take the shots for a panorama at any angle of the tripod /monopod as long as you maintain this angle during the whole round of the shots for that panorama. The correct vertical alignment can be easily achieved within PTgui.
1. Stitch and optimize the panorama as usual. Don't worry about the wrong vertical alignment at this stage.
2. Go to the control points Tab and choose an image with a clear visible vertical line, like a building corner which you could assume to be vertical. Set manually a control point on this corner like in the next screen shot. I have chosen the left corner of the white building
3. Then go to the Optimizer Tab and tick the Pitch and Roll of that image where you have set the vertical control points. ( in this case Image 0) and click the Run Optimizer button.
You will get the same optimization values but your panorama editor window will show immediately the changes.
Now you can see that the aligned building corner is vertical , but unfortunately the whole panorama is still not vertically aligned. This happens sometimes and depends on which corner you have chosen by chance. In this case it is necessary to make a second alignment. Go back to the Control Points Tab and choose another second vertical line for the alignment process.
Run the optimizer as before with the same pitch and roll settings as before ( in our case Roll and Pitch on image 0 !!) and you will see in the Editor window immediately the perfectly aligned panorama.
HINT: by moving the little triangle at the bottom of the editor window you can display a grid which comes handy to check the vertical alignment of a panorama.
1. Stitch and optimize the panorama as usual. Don't worry about the wrong vertical alignment at this stage.
2. Go to the control points Tab and choose an image with a clear visible vertical line, like a building corner which you could assume to be vertical. Set manually a control point on this corner like in the next screen shot. I have chosen the left corner of the white building
3. Then go to the Optimizer Tab and tick the Pitch and Roll of that image where you have set the vertical control points. ( in this case Image 0) and click the Run Optimizer button.
You will get the same optimization values but your panorama editor window will show immediately the changes.
Now you can see that the aligned building corner is vertical , but unfortunately the whole panorama is still not vertically aligned. This happens sometimes and depends on which corner you have chosen by chance. In this case it is necessary to make a second alignment. Go back to the Control Points Tab and choose another second vertical line for the alignment process.
Run the optimizer as before with the same pitch and roll settings as before ( in our case Roll and Pitch on image 0 !!) and you will see in the Editor window immediately the perfectly aligned panorama.
HINT: by moving the little triangle at the bottom of the editor window you can display a grid which comes handy to check the vertical alignment of a panorama.
